1. Field of the Invention
The present invention relates to a method for manufacturing vegetable juice and the like with decreased nitrate ions. More specifically, it relates to the method for manufacturing vegetable juice and the like wherein the nitrate ions are efficiently decreased in vegetable juice, vegetable extract, vegetable extract concentrate and the like, having carrot as ingredient.
2. Related Art Statement
Plants absorb nitrate nitrogen as nutrient to make amino acids and proteins. As such, nitrate nitrogen is a constituent that is indispensable for the plant, but at the same time, if nitrogen is supplied excessively in amounts that are more than the quantity necessary for growth, or if the balance with other nutrients such as phosphorus, potassium, calcium and magnesium collapses, or if photosynthesis does not proceed due to insufficient illumination, the entirety of the nitrate nitrogen that was absorbed is not metabolized into proteins and amino acids, and remains inside the body of the plant as is, in the form of nitrate nitrogen (nitrate ion).
When the nitrate nitrogen (nitrate ion) that remains inside the plant body is ingested inside the body of a human, a portion thereof is changed into nitrite ion inside the mouth and binds to amine to become “nitrosamine”, a carcinogenic substance. Furthermore in the blood, it binds to hemoglobin, which transports oxygen, to become “nitroso hemoglobin”, which is said to be a cause for triggering asphyxiation. In addition, nitrate nitrogen is also known as a causal substance of blood diseases in infants, such that decreasing nitrate ions in vegetables, vegetable juice and the like is desired.
The method of boiling the plant to achieve the decrease is well known as a method for decreasing nitrate ions. Boiling is said to allow the removal of approximately 30 to 45% of nitrate ions in case of leaf and stem vegetables and approximately 20% in case of root vegetables.
A thorough precaution is taken regarding the control of nitrate ion concentration also in the field of vegetable juice manufacturing, such that vegetable ingredients with as low as possible nitrate ion concentration are selected and used, or, methods have been adopted whereby the vegetables are blanched (boiled), or nitrate ions are adsorbed and eliminated by ion exchange treatment (see Japanese Patent Application Laid-Open No. 11-290041 and Japanese Patent Application Laid-Open No. 10-229858).